Related Experiment Video
Updated: Mar 18, 2026

Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade
Published on: August 14, 2019
Transaminase and Norcoclaurine Synthase One-Pot Cascades Towards (1S)-Tetrahydroisoquinolines
Jianxiong Zhao1, Yeke Ni1,2, Yu Wang1
1Department Chemistry, University College London, London, UK.
Abstract:
Tetrahydroisoquinolines (THIQs) are an important group of alkaloids, and many of these natural products and non-natural analogues are biologically active. For this reason, concise stereochemical synthetic routes are of significant interest. One strategy has been to use the Pictet-Spenglerase enzyme norcoclaurine synthase (NCS) with an arylethylamine and aldehyde in a single step reaction, alternatively enzyme cascades have been developed. The use of a transaminase (TAm) potentially provides efficient access to the aldehyde component required in NCS cascades, but currently suffers from limited substrate tolerance, in part due to potential complexities with the formation of mixed products. Here we present the development of a TAm-NCS cascade using structurally diverse primary amines to form (1S)-6,7-dihydroxy-THIQs via the generation of, in particular, aliphatic aldehyde intermediates in situ. Application of the one-pot cascade with amines successfully generated the corresponding products in up to >99% enantiomeric excess and 83% isolated yields. The cascade was also extended with a tyrosinase to produce a 3-hydroxymethylene substituted THIQ.
Related Concept Videos
Phase II Reactions: Miscellaneous Conjugation Reactions
A key example involves the conjugation of cyanide ions, which impair cellular respiration and alter hemoglobin into non-oxygen-carrying cyanmethemoglobin. To neutralize this threat, a sulfur atom from thiosulphate is transferred to the cyanide ion, catalyzed by the enzyme rhodanese, resulting in an inactive compound called thiocyanate. The production of...
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
Phase II Reactions: Sulfation and Conjugation with α-Amino Acids
Drug Metabolism: Phase II Reactions
Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
